This invention relates to the field of metal refining. More particularly, this invention relates to an apparatus for guiding and replacing lances, particularly those lances intended for immersion into a metal melt.
Over the past few decades, processes have been developed wherein iron melts are desulphurized by the addition of materials which are capable of forming compounds with the sulphur in the melt at high temperatures and under certain reducing conditions. These additive materials are pulverized into granular form and are introduced into the melt in suitably proportioned quantities by means of an immersion lance and a carrier gas, preferably argon.
A process similar to the above and an associated apparatus for the desulphurization of iron melts is described in European patent application No. 0 013 550, which is incorporated herein by reference. Moreover, a new type of apparatus for the introduction of immersion lances into the melt is described in European patent applications Nos. 0 056 942 and 0 056 944, which are incorporated herein by reference.
Unfortunately, these well known types of desulphurization apparatii exhibit a number of problems and difficulties which have thus far not been satisfactorily resolved. One such problem is that the immersion lance should be held as rigidly as possible during the material injection process so that no undesirable or harmful vibrations occur within the apparatus. A second problem is that, until now, it has not been possible to replace the lances as rapidly as desired, thereby resulting in less efficient and slower treatments for successive iron melts within the vessel or ladle.
A further deficiency of the prior art methods and apparatus for the desulphurization of iron melts is that the operation of automatically connecting the blowing lance to the gas supply head has necessitated the providing of movable electrical leads or pneumatic or hydraulic pipes for the supply of energy to the coupling mechanism.